A comparative study of the performance of two types of adsorbent (Streamline Quartz Base and Upfront Matrices), derivatized with the same affinity ligand (RPAP) to recover C595 diabody fragment (dbFv) from Escherichia coli lysates has been undertaken. Both streamline and Upfront Matrices are characterized by a particle size range of 100-300 mu m. Streamline has a density of 1.20 g cm(-3) and ligand concentration of 0.85 mu mol ml(-1). Upfront has a density of 1.35 g cm(-3) and ligand concentration of 0.83 mu mol ml(-1). The release of C595 dbFv from E coli cells was achieved by a chemical lysis method. The recovery performance of both adsorbents was evaluated in terms of operational productivity and elution yield of C595 dbFv in packed bed (clarified feedstock) and expanded bed (unclarified and clarified feedstock) chromatography systems. Streamline and Upfront adsorbents exhibited diabody operational productivities of 131 and 202 mg l(-1), respectively, with an elution yield of 92 and 94%, respectively, in packed bed operation. Streamline and Upfront adsorbents exhibited diabody operational productivities of 54.5 and 123.7 mg l(-1), respectively, with an elution yield of 89 and 92%, respectively, in expanded bed operation. (c) 2006 Elsevier Ltd. All rights reserved.